Dolly retainer



A; E. PETER DOLLY RETAINER Dec, 27, 1927.

Filed Feb 11 1927 X i If Y L\\ INVENTOR.

HIS ATTOR Ey Patented Dec. 27, 1927.

1 rant UNITED STATES PATENT OFFICE,

i ARTHUR E. PETERS, OF LITTLETON, COLORADO, ASSIGLTOR TO INGERSOLIi-RAND COMQ V PANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OEI Q'EW DOLLY RnrAiivER.

Application filed February 11, 1927. Serial No. 167,575.

This invention relates to drill sharpeners, but more particularly to a dolly retainer for fluid actuated drill sharpeners and the lake.

()ne object or the invention is to protect- 5 the dolly spring against the effects of the diii'erent stresses to which said spring is subjected during the reciprocation of the dolly, thus lessening the chances of breakage in retainers of this type. Other objects will be in part obvious and in part pointed out hereinafter.

The invention consists of the combination of elements and arrangement of parts substantially as hereinafter described and claimed and illustrated inthe accompanying drawings, in which Figure lis a sectional view in elevation of a portion of a drill sharpener showing t-h retainer applied'thereto, i Figure 2 is an endelevation, and

Figure 3 is an elevation in section taken through Figure 1 onthe line 33 looking in the direction indicated by the arrows.

Referring to the drawings, in which only so much of a drill sharpener is shown aswill serve to illustrate the invention and its application, a cylinder A supports a front head B and is provided with a reciprocatory haminer piston C. The hammer piston G has a plain forward extension D slidable through a front cylinder washer E and is adapted to reciprocate into a bore F of the front head B. Dis osed slidably in the front end of the front ead B is adolly H having a reduced bore F of the fronthead B to receive the blows of the hammer piston C. Preferably a port G is formed in the front head B to revent the formation of a cushion in the ore F. 1

The outer or forming face K of the dolly H may be of any suitable formation to form a corresponding face on the end-of a'drill steel (not shown) and which drill steel may be securely held in operative position by suitable devices independent of the drill sharpener. It is, however, to be understood that the dolly illustrated in the drawings does not form any part of the inventionand is shown only for illustrative purposes.

Suitable means are provided for insuring the retention of the dolly in the front head B. These means in the present instance coinprise a U-shaped loop L consisting of a pair of converging legs P connected by an hitsrearward extension J which projects into the gral intermediate portion Q which, in its operative position, is adapted to lie in and engage a transverseslot H in the periphery of the dolly I-I.

In order to produce the necessary tension on the loop Lto hold the dolly 'l-l norinally in retracted position, the loop L is provided with a pair of springs R and S which have at their inner ends upwardly projecting eirtensions T adapted to lie in the same longitudinal plane as the legs P of the loop L. Theou-ter ends of the springs R and S are in this instance provided with rearwardly extending side arins U carrying at their rearward ends hooks Vto engage pivotal trun nions W preferably carried by the front head B. The trunnions WV are so spaced with respect to a flange X on the front head that only sufficient clearance exists between the trunnions and said flange to enable the hooks V to be hooked over the t-runnions W. With the trunnions W thus located on the iront head, the hooks, in their operative position, will bear against the flange X and will be held thereby against unintentional displacement from the trunnions.

Heret-oiore, springs of this type when eniployed for the purposes described have been incapable oif rendering service for any considerable period of time, the reason for this being that springs formed of wire of sufficiently small diameter to provide the necessary resiliency are usually incapable of withstanding the various stresses to which SUGlISpil-I-IgS are subjected during the operation otthe sharpener. The present invention entirely eliminates such breakage of the dolly springs and for this reasonthe retainer is termed of separate members held and guided in operative position by suitable guide couplings designated generally by Y. The outer casings or guide sleeves Z of the couplings Y are provided at each end with relatively large recesses 6 divided by an intermediate wall 0. Inopposite sides of the walls 0 are formed sinall adjacent extremities of these elements. The fiber bushings e are preferably of somewhat smaller diameter than the recesses b to enable rubber tubes gto be disposed about the a said bushings for the purpose of cushioning such relatively angular movementas may occur between the legs P and the extensions T during the reciprocations of the dolly H.

In the present instance the bushings e and the tubes g are of somewhat less length than therecessesb to enable the ends it of the sleeves }Y to be crimped over the ends of the bushings for the purpose of retaining said bushings and said tubes in the recesses. The ends it of the sleeves Y, how ever, are preferably spaced at suificient distance from the legs and extensions to enable said legs and extensions to move freely in a lateral direction within the recesses?) without interference from. the ends it.

The relativeangular positions of the extensions T and the side arms U is preferably such that when the loop L is disposed in the slot H and the hooks V are anchored on the trunnions W, a considerable tension y will be set up in the springs R and S tending at all. times to force the dolly H to its rearwardmost limiting position in the front headB. a

The present invention has been found to function in any unusually 'efiicient manner and, owing to the resilient couplings which connectthe loop L to the springs 1t "and S,

breakage of the retainer has been entirely eliminated.

due to the tension set up therein, carry the dolly rearwardly into the front head to a position to receivethe blows of the hammer piston C. i a

Iclaim: i

1. A retainer for a dolly comprising a loop adapted to engage the dolly, a spring for normally holding the dolly inretracted position, means for anchoring the spring to a drill sharpener, and flexible connecting means connecting the spring to the loop.

2. A retainer for a dolly comprising a loop adapted to engage the dolly, a separate spring for normally holding the dolly in retracted positiomlmeans for anchoring the spring to a drill sharpener, and removable flexible connecting means connecting the spring to the loop.

8. A retainer for a dolly comprising a loop adapted to engage the dolly, a separate spring holding the dolly mirmally in retracted position, means on the spring for anchoring said sprin to a drill sharpener, and" sition, meanson the spring lo' anchoring said spring to a drill sharpener, and yield able connecting means connecting the spring 1 to the loop. a i a 5. it retainer tor a dolly comprising a loop adapted to engage-tho dolly, a spring holding the dolly normally in retracted position,

means on the spring for anchoring said spring to a drill sharpener, and transversely yieldable CGHDBClZIDg' means connecting the spring to the loop.

6. A retainer for a dolly comprising aloop adapted to engage the dolly, springs holding thedolly normally in retracted position, side arms integral with the springs foranchoring said springs to a drill sharpener, and yield able connecting means connecting the springs to the loop.

7. A retainer for adolly comprising a U shaped loop to engage the dolly, springs normally holding the dolly in retracted position,

extensions at one end of the springs, side, arms at the other end oi the springs anchor- V ing the springs to a drill sharpener, and connecting means forming flexible connect ons may between the extensions and the terminals ,of

the loop.

r 8. A retainer for a dolly holding the dolly in retracted position, ex;

tensions at the inner ends of the coil springs,

side arms at the outer ends of the coil springs for anchoring the coil springs to a drill sharpener, and sleevesconnecting the legs or the loop to the spring extensions.

9. A retainer for a dolly comprising a loop adapted to engage the dolly, springs holding the dolly normally in retracted position, side arms integral with the springs ii'or anchoring said springs to a drill sharpener, sleeves connecting the ends of the loop to the springs, and yieldable means in the sleeves to permit relative angular movement between the springs and the loop.

a 10. A retainer for a dolly comprisin a U shaped loop to engage the dolly, said loop having converging logs, springs holding the dolly normally in retracted position, extensions on thesprings, arms on the springs having hooks for anchoring the springs to a drill sharpener, sleeves holding and guiding the extensions and the said legs normally coaxial with respect to each other, yieldable means in the sleeves to cushion relative angular movement between the legs and the ex- Comprising a U shaped loop to engage the dolly, coil springs tensions, and means in the sleeve holding the adjacent ends of the legs and the extensions against relative transverse movement.

11. A retainer for a dolly comprising a U- shaped loop to engage the dolly, said loop having converging legs, springs holding the dolly normally in retracted position, extensions on the springs, arms on the springs having hooks for anchoring the springs to a drill sharpener, sleeves to receive the extensions and the legs, bushings in the sleeves slidably guiding the extensions and the legs, and rubber tubesencircling the bushings to cushion relative angular movement between the extensions and the legs.

12. A retainer for a dolly comprising a U shaped loop to engage the dolly, said loop having converging legs, springs holding the dolly normally in retracted position, extensions at the inner ends of the springs, arms at the outer ends of the springs having hooks at thBlYtOlll'llDZllS for anchoring the springs pivotally to a drill sharpener, sleeves having recesses in their, ends for the reception of the extensions and the legs, fiber bushings in the recesses to slidably guide the extensions and the legs, rubber tubes encircling the bushings to cushion relative angular movement be-,

tween the legs and the extensions, and means in the sleeves holding the adjacent ends of the legs and extensions coaxial with respect to each other.

In testimony whereof I have signed this specification.

ARTHUR E. PETERS. 

